Magnetic Anisotropy of Ion-Implanted (100), (110) Garnet Films

Anisotropy changes caused by He
⁺
and H
₂
⁺
implantations in (100), (110), and (111) magnetic garnet films have been studied. In (100) films, in striking contrast to (111) films, uniaxial anisotropy field changes were almost the same for He
⁺
and H
₂
⁺
implantations. In (110) films, the orthorhombic anisotropy parameter B changed greatly with H
₂
⁺
implantations, consistent with anisotropy changes in (111) films. The change in parameter A for He
⁺
-implanted (110) films was of the same order as for H
₂
⁺
implantations. Magnetocrystalline anisotropy K
₁
in H
₂
⁺
implanted films was determined from the angular dependence of (100) in-plane resonance fields. The sign of K
1
changed to positive with H
₂
⁺
implantation. It was found that H
₂
⁺
implantations have a great effect on λ
₁₁₁
and K
₁
, but have little influence on λ
₁₀₀
.